EP0779510A2 - Method and apparatus for analysis of particulate content of gases - Google Patents
Method and apparatus for analysis of particulate content of gases Download PDFInfo
- Publication number
- EP0779510A2 EP0779510A2 EP96308384A EP96308384A EP0779510A2 EP 0779510 A2 EP0779510 A2 EP 0779510A2 EP 96308384 A EP96308384 A EP 96308384A EP 96308384 A EP96308384 A EP 96308384A EP 0779510 A2 EP0779510 A2 EP 0779510A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- particles
- substrate
- frequency
- analysis
- gas
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000007789 gas Substances 0.000 title claims abstract description 50
- 238000004458 analytical method Methods 0.000 title claims abstract description 33
- 238000000034 method Methods 0.000 title claims description 42
- 239000002245 particle Substances 0.000 claims abstract description 56
- 239000013078 crystal Substances 0.000 claims abstract description 20
- 230000010355 oscillation Effects 0.000 claims abstract description 14
- 238000005070 sampling Methods 0.000 claims abstract description 14
- 238000005367 electrostatic precipitation Methods 0.000 claims abstract description 9
- 238000010438 heat treatment Methods 0.000 claims abstract 3
- 239000000758 substrate Substances 0.000 claims description 33
- 238000012544 monitoring process Methods 0.000 claims description 16
- 238000005259 measurement Methods 0.000 claims description 13
- 239000000463 material Substances 0.000 claims description 11
- 239000012717 electrostatic precipitator Substances 0.000 claims description 8
- 230000008859 change Effects 0.000 claims description 7
- 229910052751 metal Inorganic materials 0.000 claims description 7
- 239000002184 metal Substances 0.000 claims description 7
- 230000003647 oxidation Effects 0.000 claims description 7
- 238000007254 oxidation reaction Methods 0.000 claims description 7
- 239000011248 coating agent Substances 0.000 claims description 6
- 238000000576 coating method Methods 0.000 claims description 6
- 230000000694 effects Effects 0.000 claims description 6
- 230000003197 catalytic effect Effects 0.000 claims description 4
- 239000011236 particulate material Substances 0.000 claims description 4
- 230000008021 deposition Effects 0.000 claims description 3
- 238000001556 precipitation Methods 0.000 claims description 3
- 238000000691 measurement method Methods 0.000 claims description 2
- 230000001376 precipitating effect Effects 0.000 claims 1
- 238000004445 quantitative analysis Methods 0.000 abstract description 6
- 238000004451 qualitative analysis Methods 0.000 abstract description 5
- 239000003054 catalyst Substances 0.000 abstract 1
- 230000008569 process Effects 0.000 description 10
- 239000013618 particulate matter Substances 0.000 description 8
- 238000012545 processing Methods 0.000 description 5
- 238000012360 testing method Methods 0.000 description 5
- 230000002776 aggregation Effects 0.000 description 4
- 239000000470 constituent Substances 0.000 description 3
- 238000010790 dilution Methods 0.000 description 3
- 239000012895 dilution Substances 0.000 description 3
- 238000004924 electrostatic deposition Methods 0.000 description 3
- 239000012530 fluid Substances 0.000 description 3
- 238000011010 flushing procedure Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000005054 agglomeration Methods 0.000 description 2
- 238000004220 aggregation Methods 0.000 description 2
- 239000012491 analyte Substances 0.000 description 2
- 238000009833 condensation Methods 0.000 description 2
- 230000005494 condensation Effects 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 238000013481 data capture Methods 0.000 description 2
- 238000013500 data storage Methods 0.000 description 2
- 238000000151 deposition Methods 0.000 description 2
- 239000000428 dust Substances 0.000 description 2
- 229930195733 hydrocarbon Natural products 0.000 description 2
- 150000002430 hydrocarbons Chemical class 0.000 description 2
- 238000011068 loading method Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- 239000004071 soot Substances 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- 230000003213 activating effect Effects 0.000 description 1
- 239000003570 air Substances 0.000 description 1
- 239000012080 ambient air Substances 0.000 description 1
- 229910052787 antimony Inorganic materials 0.000 description 1
- WATWJIUSRGPENY-UHFFFAOYSA-N antimony atom Chemical compound [Sb] WATWJIUSRGPENY-UHFFFAOYSA-N 0.000 description 1
- 238000001311 chemical methods and process Methods 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000004868 gas analysis Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000011005 laboratory method Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 239000012716 precipitator Substances 0.000 description 1
- 230000005180 public health Effects 0.000 description 1
- 238000003380 quartz crystal microbalance Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 229910021653 sulphate ion Inorganic materials 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 238000002411 thermogravimetry Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/02—Analysing fluids
- G01N29/036—Analysing fluids by measuring frequency or resonance of acoustic waves
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/02—Devices for withdrawing samples
- G01N1/22—Devices for withdrawing samples in the gaseous state
- G01N1/2202—Devices for withdrawing samples in the gaseous state involving separation of sample components during sampling
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/06—Investigating concentration of particle suspensions
- G01N15/0606—Investigating concentration of particle suspensions by collecting particles on a support
- G01N15/0618—Investigating concentration of particle suspensions by collecting particles on a support of the filter type
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/06—Investigating concentration of particle suspensions
- G01N15/0656—Investigating concentration of particle suspensions using electric, e.g. electrostatic methods or magnetic methods
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N5/00—Analysing materials by weighing, e.g. weighing small particles separated from a gas or liquid
- G01N5/04—Analysing materials by weighing, e.g. weighing small particles separated from a gas or liquid by removing a component, e.g. by evaporation, and weighing the remainder
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/02—Devices for withdrawing samples
- G01N1/22—Devices for withdrawing samples in the gaseous state
- G01N1/2202—Devices for withdrawing samples in the gaseous state involving separation of sample components during sampling
- G01N2001/222—Other features
- G01N2001/2223—Other features aerosol sampling devices
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/02—Indexing codes associated with the analysed material
- G01N2291/025—Change of phase or condition
- G01N2291/0256—Adsorption, desorption, surface mass change, e.g. on biosensors
Definitions
- This invention relates to a method and apparatus for analysis of particulate content of gases.
- An example of the application of the invention is to the qualitative and quantitative analysis of emissions from internal combustion engines, particularly vehicle engines, but the invention is applicable also more widely than in the automotive field.
- particulate matter in air and other gases is performed in a wide variety of industries and applications.
- exhaust emissions from automobiles and cars and trucks and lorries are measured during and post manufacture and in the aftermarket to ensure compliance with increasingly restrictive official regulations.
- the particulate matter (soot) generated by diesel engines is a focus for legislative control and is at present the subject of studies into its effects on public health. It is likely that supplementary regulations relating to the particulate content in vehicle emissions will compel automotive and other manufacturers to investigate the means to reduce such levels in original equipment.
- ensuring compliance of engines in use in the aftermarket may entail a modification to the tests carried out on a compulsory basis in many countries to determine compliance with official requirements.
- Exhaust emissions are tested on a chassis dynameter or engine test stand using the CVS (controlled volume sampling) method.
- the exhaust gases are diluted with filtered ambient air and extracted with a blower and applied to a standardised test procedure.
- the dilution inhibits condensation and agglomeration effects during sample collection. Dilution also holds the sample temperature at the level required for particulate measurement.
- Several techniques are available for particulate measurement, including gravimetric measurement, differential mobility analysis and condensation core counting. At present, the gravimetric technique is the most widely used means of assessment, but it lacks sensitivity at low particulate levels and measurement time is lengthy. All these available techniques involve relatively large and expensive equipment, which arises particularly as a result of the use of the dilution system, which simulates the physical and chemical processes which the particulate emissions undergo in the atmosphere.
- GB-A-2 270 564 discloses a method of identifying fluid materials or analytes using a piezoelectric crystal oscillator.
- the system operates on the basis of monitoring a step change in the concentration of the analyte, leading to a characteristic frequency change enabling identification of the analyte.
- the method includes an embodiment using a reverse step in concentration change.
- this disclosure in common with the other prior proposals known to the Applicants lacks any suggestion of the technical merit of monitoring the frequency change resulting from the inverse step of particulate desorbtion or removal from the piezoelectric substrate, with its attendant advantanges as disclosed herein.
- An object of the present invention is to provide a method and apparatus, particularly but not exclusively applicable to the qualitative and/or quantitative analysis of automotive emissions, providing improvements in relation to currently available equipment, notably in relation to compactness of the apparatus and/or simplicity or speed of the method and/or cost of the apparatus and/or the method, or other improvements disclosed herein or generally.
- a method and apparatus for the analysis of particulate content of gases comprises the steps of sampling the gas, removing particles from the gas sample, and subjecting the removed particles to analysis.
- the step of removal of the particles from the gas sample comprises causing the particles to be deposited on a substrate.
- the step of analysis comprises causing at least some of the deposited particles to be removed from the substrate and the application of a measurement technique to this step of removal in order to determine qualitative or quantitative information concerning the particulate content of the gas to be analysed.
- the steps of sampling and removal and analysis correspond to steps of analysis known from the use of an electrostatic precipitator.
- the step of removal of the particles is carried out by means of a electrostatic precipitation technique employing a metal-coated piezo-electric crystal forming an anode in the precipitation step. Then, some at least of the particles deposited on the electrode are removed in an oxidising step merely by application of heat and an oxidising atmosphere to the piezo-electric crystal so that qualitative and quantitative information can be obtained concerning the particles deposited.
- the embodiments of the invention provide a method and apparatus whereby a relatively simple item of electrical equipment can obtain both qualitative and quantitative data relating to particulate content of gases on a relatively rapid basis.
- apparatus 10 for analysis for particulate content of gases comprises sensor elements 12, 14, a multiplexer 16, a data capture system 18, signal processing apparatus 20 together with data storage means 22 and gas analysis
- Sensor elements 12 and 14 represent two of an optional range of elements for analysis of a variety of gases.
- Each sensor element comprises an electrode 26 as shown in Fig 2 coupled to an oscillator and electrostatic precipitator circuit 28.
- Each sensor element 12, 14 has electrode 26 mounted within a glass envelope indicated at 30, 32 in Fig 1 to which a gas to be analysed is supplied by sampling means 34.
- Sampling means 34 comprises known apparatus for extracting a volumetrically controlled sample from a gas supply and adapted to deliver same to envelopes 30, 32 containing electrodes 26.
- the electrode 26 and the associated electrostatic precipitation circuit 28 constitute removal means adapted to remove particles from the gas sample delivered to envelope 30 or 32 by sampling means 34.
- the electrode performs the removal step by electrostatic precipitation. It will also be understood that the removal means 26 and 28 also constitute deposition means adapted to deposit the particles on a substrate constituted by the electrode 26.
- further removal means adapted to remove deposited particles from the substrate or electrode 26, and such further removal means is constituted by a heater 36 which effects such removal in combination with oxidation gas supply means 38 which is adapted to supply an oxidising gas mixture to the envelopes 30, 32 for a purpose to be more fully described below, in a manner analogous to sampling means 36.
- circuits 16, 18, 20 and 22 provide a measurement function in relation to sensor elements 12 and 14 enabling measurement of the step of removal of particles from electrode 26 by the above-mentioned oxidation step for the determination of the particulate content of a gas being analysed.
- Sensor elements 12 and 14 comprise electrodes 26 as shown in Fig 2 mounted at 37, respectively, in envelopes 30, 32 which are connected to sampling means 34 and the oxidation gas supply means 38.
- Electrode 26 is in the form of a piezoelectric crystal comprising an AT-cut 10 megahertz crystal 40 having gold-plated electrodes and connected to oscillator circuit 28.
- Crystal 40 has a coating 42 of a catalytic metal eg platinum or antimony and forms the anode in the electrostatic precipitator circuit 28.
- electrode 26 causes particulate matter (shown diagrammatically at 44) to become charged and to move towards and adhere to crystal 40.
- Crystal 40 becomes loaded with the particulate matter to an extent that reflects the particulate density in the gas mixture to be analysed. This mass loading of the crystal 40 produces a measurable negative shift (reduction) in the oscillation frequency of crystal 40 in association with oscillator circuit 28. A frequency shift of the order of some hundreds of hertz can be expected.
- Fig 1 of the drawings it will be seen that sensor elements 12 and 14 are shown connected to multiplexer 16.
- the multiplexer and following data processing stages 18, 20 and 22 are adapted to receive frequency information from electrode 26.
- the oscillator and electrostatic precipitator circuits 28 seen in Fig 2 are not shown. It is to be understood that, of course, these circuits remain in operational connection to electrode 26 in accordance with the requirements of the analysis process described herein.
- Sampling means 34 delivers the gas to be analysed to envelopes 30, 32 and thus to the electrodes 26 therein. These effect an electrostatic deposition of particulate content of the gas samples onto the material of the electrode where it is captured by the catalytic coating 42.
- Sampling means 34 comprises a pump for gas delivery purposes. It is believed that the construction and operation of the oscillator and electrostatic precipitator circuit 28 will be well known to those skilled in the technical field and therefore these are not further described here.
- Oscillator circuit 28 is activated to establish a preliminary oscillation frequency prior to the electrostatic deposition stage. Then the electrostatic precipitator circuit is energised to effect such precipitation, whereupon there is a frequency shift as described above, in accordance with the mass of particulate deposited.
- the step of removal of the particulate from the electrodes 26 is effected by activating the supply 38 of oxididation gas so that the gas to be sampled is flushed out and electrode 26 is surrounded by an oxidising atmosphere.
- heater 36 is energised.
- the heater may, for example, be a laser beam, focused upon the electrode whereby the deposited particles are caused to be removed from the electrode by oxidation in the elevated temperature and oxidising atmosphere conditions thus-provided.
- the oscillation frequency of electrodes 26 and oscillator circuit 28 continue to be monitored by the data-processing system 16, 18, 20 and 22.
- the resultant shift in oscillation frequency occurring in such a situation is shown, for one typical example, in Fig 3 where the mass of material deposited is plotted against time. This plot is obtained during the oxidation step since mass can be seen here to reduce substantially with time.
- the graphic presentation in Fig 3 is derived from the frequency shift information provided to the data handling system, 16, 18, 20 and 22.
- the profile of the plot 46 enables interpretation of the presence of particulates on a qualitative basis.
- the dip shown at 48 in Fig 3 corresponds to the removal of the soluble organic fraction (SOF) from the electrode.
- the features of the plot identified at 50 are characteristic of the break-up of particulate content.
- the method permits analysis of the agglomeration (total mass of material deposited and its removal), and the sulphate content and the soluble organic fraction.
- the shape of the curve at location 50 is characteristic of the break-up of agglomerated particulate matter.
- flushing or de-gasing of the sensor elements 12 and 14 can be accomplished by reversing the pularity of the precipitator and flushing the envelopes 30, 32 with nitrogen.
- the sensor elements 30 and 32 may be provided with specific abilities to absorb and permit analysis of specific hydrocarbons, or a family of hydrocarbons, by varying the material of the coating on the electrode. Accordingly, if so required, an array of similar piezoelectric electrodes 26 may be provided in order to deal with the analysis of particular gas constituents. Such provision is indicated at 50 in Fig 1.
- the alternative curve dip profiles shown at 52 and 54 enable interpretation of specific constituent materials in the same manner as the profiles shown at 48 and 50, and notably in relation to the particle size of an identified constituent, the dip profiles 52, 54, 56 each being characteristic of a range of particle sizes.
- Such interpretation is effected by the data processing apparatus shown in Fig 1 namely multiplexer 16, data capture system 18, signal processing system and data storage system 22, on the basis of prior test work using known gas samples, of known particle size.
- thermographic analysis apparatus in order to provide additional data in relation to the analysis of the gas in question.
Landscapes
- Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Immunology (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Analytical Chemistry (AREA)
- Pathology (AREA)
- Dispersion Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Biomedical Technology (AREA)
- Molecular Biology (AREA)
- Acoustics & Sound (AREA)
- Sampling And Sample Adjustment (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
Description
- This invention relates to a method and apparatus for analysis of particulate content of gases. An example of the application of the invention is to the qualitative and quantitative analysis of emissions from internal combustion engines, particularly vehicle engines, but the invention is applicable also more widely than in the automotive field.
- The analysis of particulate matter in air and other gases is performed in a wide variety of industries and applications. In the automotive sector, exhaust emissions from automobiles and cars and trucks and lorries are measured during and post manufacture and in the aftermarket to ensure compliance with increasingly restrictive official regulations. The particulate matter (soot) generated by diesel engines is a focus for legislative control and is at present the subject of studies into its effects on public health. It is likely that supplementary regulations relating to the particulate content in vehicle emissions will compel automotive and other manufacturers to investigate the means to reduce such levels in original equipment. Likewise, ensuring compliance of engines in use in the aftermarket may entail a modification to the tests carried out on a compulsory basis in many countries to determine compliance with official requirements.
- Currently available equipment for determination of particulate content of engine emissions, as used in Europe in the aftermarket, is based upon the measurement of opacity using a comparatively simple and inexpensive instrument. Another technique uses a volumetrically-controlled sample of engine emission gas which is drawn through a filter element and the degrees of discolouration of the filter element is used as an index for the amount of soot emitted. Both these techniques are unsuitable for the quantitative analysis of sub-micron particles and provide no qualitative information, as such, at all.
- As regards engine emission tests carried out during and after engine manufacture, these are more complex. Exhaust emissions are tested on a chassis dynameter or engine test stand using the CVS (controlled volume sampling) method. In this method, the exhaust gases are diluted with filtered ambient air and extracted with a blower and applied to a standardised test procedure. The dilution inhibits condensation and agglomeration effects during sample collection. Dilution also holds the sample temperature at the level required for particulate measurement. Several techniques are available for particulate measurement, including gravimetric measurement, differential mobility analysis and condensation core counting. At present, the gravimetric technique is the most widely used means of assessment, but it lacks sensitivity at low particulate levels and measurement time is lengthy. All these available techniques involve relatively large and expensive equipment, which arises particularly as a result of the use of the dilution system, which simulates the physical and chemical processes which the particulate emissions undergo in the atmosphere.
- As to laboratory techniques for particulate measurement, many methods have been developed including the use of the quartz crystal microbalance and the electrostatic precipitator. To the best of the Applicant's knowledge these techniques have not been applied to the qualitative and/or quantitative analysis of automotive emissions and the like.
- There is disclosed in US 3,478,573 (King) a piezoelectric crystal having an integral heater and suitable for use in measuring devices such as gas analysers. An electronic oscillator is controlled by the piezoelectric material. A coating on the piezoelectric material is adapted to interact with at least one component of a fluid to be analysed and the resulting changes in the frequency of the piezoelectric material as it interacts with the fluid are monitored for analytical purposes. The process is subject to the limitations evident from the development of the present invention including inferior sensitivity and less clear-cut simplicity of construction as compared with the analytical desorbtion process of the embodiments of the present invention.
- There is disclosed in US 5,056,355 (Hepher) a device for monitoring dust or other particulate material in gas and comprising the use of a piezoelectric sensor and the step of monitoring variations in the resonant frequency of the sensor as induced by the aggregation of dust on the sensor. The system of this prior proposal is likewise subject to the limitation highlighted by the embodiments of the present invention and arising from the use of a technique in which the frequency monitoring step is applied to the process of particulate aggregation or addition to the sensor, as opposed to the converse system employed in the embodiments of the invention.
- GB-A-2 270 564 (GEC Marconi) discloses a method of identifying fluid materials or analytes using a piezoelectric crystal oscillator. The system operates on the basis of monitoring a step change in the concentration of the analyte, leading to a characteristic frequency change enabling identification of the analyte. The method includes an embodiment using a reverse step in concentration change. However, this disclosure in common with the other prior proposals known to the Applicants lacks any suggestion of the technical merit of monitoring the frequency change resulting from the inverse step of particulate desorbtion or removal from the piezoelectric substrate, with its attendant advantanges as disclosed herein.
- US patents
- 3,561,253
- 4,561,286
- 4,041,768
- 4,446,720
- The disclosure in US 5,056,355 is taken as the basis for the two-part form of claim 1 hereof.
- An object of the present invention is to provide a method and apparatus, particularly but not exclusively applicable to the qualitative and/or quantitative analysis of automotive emissions, providing improvements in relation to currently available equipment, notably in relation to compactness of the apparatus and/or simplicity or speed of the method and/or cost of the apparatus and/or the method, or other improvements disclosed herein or generally.
- According to the invention a method and apparatus for the analysis of particulate content of gases comprises the steps of sampling the gas, removing particles from the gas sample, and subjecting the removed particles to analysis.
- In accordance with the invention, the step of removal of the particles from the gas sample comprises causing the particles to be deposited on a substrate. Further in accordance with the invention, the step of analysis comprises causing at least some of the deposited particles to be removed from the substrate and the application of a measurement technique to this step of removal in order to determine qualitative or quantitative information concerning the particulate content of the gas to be analysed.
- The steps of sampling and removal and analysis correspond to steps of analysis known from the use of an electrostatic precipitator. By the additional steps of causing the particles to be deposited on a substrate and some at least of these to be subsequently removed while analysis takes place, in accordance with the invention, enables a simple and rapid determination of information concerning the qualitative and/or quantitative content of the gas to be analysed, thereby reducing the need for subsequent flushing or cleaning before repeat use.
- Thus, in one embodiment, the step of removal of the particles is carried out by means of a electrostatic precipitation technique employing a metal-coated piezo-electric crystal forming an anode in the precipitation step. Then, some at least of the particles deposited on the electrode are removed in an oxidising step merely by application of heat and an oxidising atmosphere to the piezo-electric crystal so that qualitative and quantitative information can be obtained concerning the particles deposited.
- This is achieved by connecting the electrode to an oscillator circuit and monitoring the changes in the frequency of oscillation as the particles are initially deposited and subsequently removed. Interpretation of the profile of the graph of rate of change of mass of the electrode provides a basis for determining the identity and/or quantitative presence of materials deposited and removed from the electrode.
- Accordingly, the embodiments of the invention provide a method and apparatus whereby a relatively simple item of electrical equipment can obtain both qualitative and quantitative data relating to particulate content of gases on a relatively rapid basis.
- While the principal applications of the invention are expected to be in the testing of automobile exhaust emissions, both at the time of manufacture and in the automotive aftermarket, it is expected that a variant of the embodiments could be developed for environmental or industrial pollution monitoring.
- Embodiments of the invention will now be described by way of example with reference to the accompanying drawings in which :
- Fig 1 shows in block diagram form an embodiment of apparatus according to the invention;
- Fig 2 shows an elevation view of an electrode forming part of the apparatus of Fig 1; and
- Fig 3 shows a plot of mass against time for a part of the process carried out by the apparatus of Figs 1 and 2, relating to removal of particles from the electrode of Fig 2.
- As shown in the drawings,
apparatus 10 for analysis for particulate content of gases comprisessensor elements multiplexer 16, adata capture system 18,signal processing apparatus 20 together with data storage means 22 and gas analysis - output means 24. These general elements of the apparatus will now be described in more detail.
-
Sensor elements electrode 26 as shown in Fig 2 coupled to an oscillator andelectrostatic precipitator circuit 28. - Each
sensor element electrode 26 mounted within a glass envelope indicated at 30, 32 in Fig 1 to which a gas to be analysed is supplied by sampling means 34. - Sampling means 34 comprises known apparatus for extracting a volumetrically controlled sample from a gas supply and adapted to deliver same to
envelopes 30, 32 containingelectrodes 26. - The
electrode 26 and the associatedelectrostatic precipitation circuit 28 constitute removal means adapted to remove particles from the gas sample delivered toenvelope 30 or 32 by sampling means 34. The electrode performs the removal step by electrostatic precipitation. It will also be understood that the removal means 26 and 28 also constitute deposition means adapted to deposit the particles on a substrate constituted by theelectrode 26. - Further in relation to terminology employed in the definition of the present invention, there is provided further removal means adapted to remove deposited particles from the substrate or
electrode 26, and such further removal means is constituted by aheater 36 which effects such removal in combination with oxidation gas supply means 38 which is adapted to supply an oxidising gas mixture to theenvelopes 30, 32 for a purpose to be more fully described below, in a manner analogous to sampling means 36. - Finally, it will be understood that
circuits sensor elements electrode 26 by the above-mentioned oxidation step for the determination of the particulate content of a gas being analysed. - Turning now to a more detailed description of the above-mentioned main features of the
apparatus 10,sensor elements -
Sensor elements electrodes 26 as shown in Fig 2 mounted at 37, respectively, inenvelopes 30, 32 which are connected to sampling means 34 and the oxidation gas supply means 38.Electrode 26 is in the form of a piezoelectric crystal comprising an AT-cut 10megahertz crystal 40 having gold-plated electrodes and connected tooscillator circuit 28.Crystal 40 has acoating 42 of a catalytic metal eg platinum or antimony and forms the anode in theelectrostatic precipitator circuit 28. In use,electrode 26 causes particulate matter (shown diagrammatically at 44) to become charged and to move towards and adhere tocrystal 40.Crystal 40 becomes loaded with the particulate matter to an extent that reflects the particulate density in the gas mixture to be analysed. This mass loading of thecrystal 40 produces a measurable negative shift (reduction) in the oscillation frequency ofcrystal 40 in association withoscillator circuit 28. A frequency shift of the order of some hundreds of hertz can be expected. - Turning to Fig 1 of the drawings, it will be seen that
sensor elements multiplexer 16. The multiplexer and following data processing stages 18, 20 and 22 are adapted to receive frequency information fromelectrode 26. For simplicity of illustration in Fig 1, the oscillator andelectrostatic precipitator circuits 28 seen in Fig 2 are not shown. It is to be understood that, of course, these circuits remain in operational connection toelectrode 26 in accordance with the requirements of the analysis process described herein. - Turning now to the general mode of operation of
apparatus 10, this is as follows. Sampling means 34 delivers the gas to be analysed toenvelopes 30, 32 and thus to theelectrodes 26 therein. These effect an electrostatic deposition of particulate content of the gas samples onto the material of the electrode where it is captured by thecatalytic coating 42. Sampling means 34 comprises a pump for gas delivery purposes. It is believed that the construction and operation of the oscillator andelectrostatic precipitator circuit 28 will be well known to those skilled in the technical field and therefore these are not further described here. -
Oscillator circuit 28 is activated to establish a preliminary oscillation frequency prior to the electrostatic deposition stage. Then the electrostatic precipitator circuit is energised to effect such precipitation, whereupon there is a frequency shift as described above, in accordance with the mass of particulate deposited. - After this deposition step in relation to particulate matter from the gas sample, there follows the step of removal of the particulate from the
electrodes 26. This is effected by activating thesupply 38 of oxididation gas so that the gas to be sampled is flushed out andelectrode 26 is surrounded by an oxidising atmosphere. Thereuponheater 36 is energised. The heater may, for example, be a laser beam, focused upon the electrode whereby the deposited particles are caused to be removed from the electrode by oxidation in the elevated temperature and oxidising atmosphere conditions thus-provided. - During this process of particulate removal from the
electrode 26, the oscillation frequency ofelectrodes 26 andoscillator circuit 28 continue to be monitored by the data-processingsystem - As the particulate material mass loading on
crystals 40 reduces, the oscillation frequency correspondingly increases. The graphic presentation in Fig 3 is derived from the frequency shift information provided to the data handling system, 16, 18, 20 and 22. The profile of the plot 46 enables interpretation of the presence of particulates on a qualitative basis. For example, the dip shown at 48 in Fig 3 corresponds to the removal of the soluble organic fraction (SOF) from the electrode. The features of the plot identified at 50 are characteristic of the break-up of particulate content. The method permits analysis of the agglomeration (total mass of material deposited and its removal), and the sulphate content and the soluble organic fraction. The shape of the curve atlocation 50 is characteristic of the break-up of agglomerated particulate matter. - After use, flushing or de-gasing of the
sensor elements envelopes 30, 32 with nitrogen. - In the above embodiment, the
sensor elements 30 and 32 may be provided with specific abilities to absorb and permit analysis of specific hydrocarbons, or a family of hydrocarbons, by varying the material of the coating on the electrode. Accordingly, if so required, an array of similarpiezoelectric electrodes 26 may be provided in order to deal with the analysis of particular gas constituents. Such provision is indicated at 50 in Fig 1. - In Fig 3 the alternative curve dip profiles shown at 52 and 54 enable interpretation of specific constituent materials in the same manner as the profiles shown at 48 and 50, and notably in relation to the particle size of an identified constituent, the dip profiles 52, 54, 56 each being characteristic of a range of particle sizes. Such interpretation is effected by the data processing apparatus shown in Fig 1 namely
multiplexer 16,data capture system 18, signal processing system and data storage system 22, on the basis of prior test work using known gas samples, of known particle size. - In a further embodiment, there may be employed a chromatagraph (not shown) in association with the thermographic analysis apparatus described above, in order to provide additional data in relation to the analysis of the gas in question.
Claims (18)
- A method of analysis of particulate content of gases comprising :a) sampling a gas to be analysed;b) removing particles from said sample;c) subjecting said removed particles to analysis; andd) said step of removing said particles comprising causing said particles to be deposited on a frequency-responsive substrate;
characterised bye) said step of analysis comprising causing at least some of said deposited particles to be at least partially removed from said frequency-responsive substrate; andf) said step of analysis further comprising applying a frequency monitoring technique to said step of at least partial removal of said particles from said substrate in order to determine information concerning the particulate content of said gas to be analysed. - A method of analysis of particulate content of gases characterised by the step of at least partially removing from a substrate particles deposited from a gas sample and the method comprising applying a measurement technique to said step of removal of particles from said substrate so as to determine information concerning the particulate content of said gas to be analysed.
- A method according to claim 1 characterised by said step of removing particles from said sample of gas to be analysed comprising causing electrostatic precipitation of said particles on said substrate.
- A method according to claim 3 characterised by said electrostatic precipitation comprising precipitating said particles on said frequency responsive substrate comprising a metal-coated piezo-electric crystal forming an anode in said precipitation step.
- A method according to claim 4 characterised by employing as said metal coating on said anode a catalytic metal.
- A method according to any one of the preceding claims characterised by said step of removal of said particles from said frequency responsive substrate comprising oxidising said particles by heating said substrate in an oxidising atmosphere.
- A method according to claim 6 characterised by said step of applying a frequency monitoring technique to said step of removal of said particles from said substrate comprising employing said substrate as an electrode in an electrostatic precipitator circuit and connecting said electrode to an oscillator circuit and determining the frequency of oscillation as a measure of the mass of particles remaining on said substrate, as said oxidation proceeds.
- A method according to claim 7 characterised by said step of determining the frequency of oscillation comprising monitoring changes in the oscillation frequency of said circuit as said measure of the mass of the particles remaining on said substrate.
- A method according to claim 8 characterised by said step of applying a frequency monitoring technique comprising determining changes in the gradient or profile of the graph of the rate of change of mass of said substrate as a basis for determining the identity and/or particle size of particulate materials deposited and removed from said substrate.
- Apparatus for the analysis of particulate content of gases comprising :a) sampling means adapted to sample a gas to be analysed;b) removal means adapted to remove particles from said sample;c) analysis means adapted to analyse said particles removed from said sample; andd) deposition means adapted to deposit said particles on a frequency-responsive substrate;
characterised bye) further removal means adapted to remove at least partially at least some of said deposited particles from said substrate; andf) frequency monitoring measurement means adapted to measure one or more aspects of said step of at least partial removal of said particles from said substrate in order to determine information concerning the particulate content of said gas to be analysed. - Apparatus for the analysis of particulate content of gases comprising a substrate adapted to receive particles to be deposited thereon from a sample of said gas to be analysed, and removal means adapted to remove at least partially at least some of said deposited particles to permit measurement means to determine information concerning the particulate content of said gas to be analysed on the basis of said removal step.
- Apparatus according to claim 10 characterised by said first removal means for removing particles from said gas sample comprising electrostatic precipitation apparatus.
- Apparatus according to claim 12 characterised by said electrostatic precipitation apparatus comprising a metal-coated piezo-electric crystal forming an anode in said electro static precipitation apparatus.
- Apparatus according to claim 13 characterised by said metallic coating of said anode comprising a catalytic metal.
- Apparatus according to any one of claims 10 to 14 characterised by said further removal means being adapted to remove at least some of said particles from said frequency responsive substrate comprising heating means for said substrate and gas supply means adapted to supply an oxidising atmosphere to said apparatus whereby said particles thereon can be heated in an oxidising atmosphere to effect oxidisation thereof.
- Apparatus according to claim 14 characterised by said frequency responsive measurement means adapted to measure an aspect of the step of removal of said particles from said substrate comprising an oscillator circuit and said substrate forming an electrode connected as an anode to said oscillator circuit, and frequency measurement means being provided to determine the frequency of oscillation of said circuit as a measure of the mass of particles remaining on said substrate as said oxidation proceeds.
- Apparatus according to claim 16 characterised by the step of employing frequency monitoring means to monitor changes in the oscillation frequency as said measure of the mass of particles deposited.
- Apparatus according to claim 17 characterised by frequency interpretation means adapted to interpret the data obtained by said monitoring step to determine changes in the gradient or profile of said graph of rate of change of mass of said substrate as a basis for determining the identity and/or quantitative presence and/or particle size of materials deposited and removed from said substrate.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP03010874A EP1353167A1 (en) | 1995-11-21 | 1996-11-20 | Method and apparatus for analysis of particulate content of gases |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GBGB9523812.7A GB9523812D0 (en) | 1995-11-21 | 1995-11-21 | Method and apparatus for analysis of particulate content of gases |
GB9523812 | 1995-11-21 |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP03010874A Division EP1353167A1 (en) | 1995-11-21 | 1996-11-20 | Method and apparatus for analysis of particulate content of gases |
Publications (3)
Publication Number | Publication Date |
---|---|
EP0779510A2 true EP0779510A2 (en) | 1997-06-18 |
EP0779510A3 EP0779510A3 (en) | 1998-05-27 |
EP0779510B1 EP0779510B1 (en) | 2004-02-04 |
Family
ID=10784230
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP03010874A Withdrawn EP1353167A1 (en) | 1995-11-21 | 1996-11-20 | Method and apparatus for analysis of particulate content of gases |
EP96308384A Expired - Lifetime EP0779510B1 (en) | 1995-11-21 | 1996-11-20 | Method and apparatus for analysis of particulate content of gases |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP03010874A Withdrawn EP1353167A1 (en) | 1995-11-21 | 1996-11-20 | Method and apparatus for analysis of particulate content of gases |
Country Status (5)
Country | Link |
---|---|
US (1) | US5892141A (en) |
EP (2) | EP1353167A1 (en) |
AT (1) | ATE259062T1 (en) |
DE (1) | DE69631465T2 (en) |
GB (1) | GB9523812D0 (en) |
Cited By (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2000046584A2 (en) * | 1999-02-02 | 2000-08-10 | Rupprecht & Patashnick Company, Inc. | Differential particulate mass monitor with intrinsic correction for volatilization losses |
EP1059521A2 (en) * | 1999-06-07 | 2000-12-13 | MIE, Inc | System and method for continuous monitoring of particulates |
WO2001001110A1 (en) * | 1999-06-23 | 2001-01-04 | Avl List Gmbh | Arrangement for quantitative and qualitative analysis of particles in gases |
US6205842B1 (en) | 1999-02-02 | 2001-03-27 | Rupprecht & Patashnick Company, Inc. | Differential particulate mass monitor with intrinsic correction for volatilization losses |
EP1251344A2 (en) * | 2001-04-18 | 2002-10-23 | AVL List GmbH | Process of measuring aerosol particles in gas samples |
US6502450B1 (en) | 1999-05-10 | 2003-01-07 | Rupprecht & Patashnik Company, Inc. | Single detector differential particulate mass monitor with intrinsic correction for volatilization losses |
EP1283419A2 (en) * | 2001-08-11 | 2003-02-12 | Robert Bosch Gmbh | Device for determining the concentration of particles in a exhaust gas flow |
EP1316796A1 (en) * | 2001-11-26 | 2003-06-04 | AVL List GmbH | Apparatus and method of determining the non-volatile portion of aerosol particles in a gas sample |
JP2003532056A (en) * | 2000-04-05 | 2003-10-28 | ザ チャールズ スターク ドレイパー ラボラトリー インク | Apparatus and method for measuring mass of substance |
WO2003100390A2 (en) * | 2002-05-24 | 2003-12-04 | Symyx Technologies, Inc. | High throughput microbalance and methods of using same |
FR2850460A1 (en) * | 2003-01-23 | 2004-07-30 | Toulouse Inst Nat Polytech | Method for testing materials by thermogravimetry, comprises heating and cooling samples in presence of controlled atmosphere and weighing them during the cycles with high precision integral balances |
JP2005172831A (en) * | 2003-12-10 | 2005-06-30 | Robert Bosch Gmbh | Apparatus for detecting particles in exhaust gas |
DE102006032106A1 (en) * | 2006-07-11 | 2008-01-17 | Siemens Ag | Soot sensor and operating method |
US7721590B2 (en) | 2003-03-21 | 2010-05-25 | MEAS France | Resonator sensor assembly |
GB2506991A (en) * | 2012-09-21 | 2014-04-16 | Msp Corp | Measuring the mass of particulate matter in a gas |
WO2015189230A1 (en) * | 2014-06-10 | 2015-12-17 | Koninklijke Philips N.V. | Aerosol mass sensor and sensing method |
CN110426310A (en) * | 2019-07-31 | 2019-11-08 | 长春黄金研究院有限公司 | A kind of Fire Assaying analysis method |
US11085861B1 (en) | 2014-03-03 | 2021-08-10 | Msp Corporation | Apparatus for real-time size-distributed measurement of aerosol mass concentration |
Families Citing this family (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6111512A (en) * | 1997-03-13 | 2000-08-29 | Nippon Telegraph And Telephone Corporation | Fire detection method and fire detection apparatus |
WO2000014518A1 (en) * | 1998-09-04 | 2000-03-16 | Ceramem Corporation | Simple particulate emissions measuring instrument, system and method |
AT411628B (en) * | 1999-12-14 | 2004-03-25 | Avl List Gmbh | ARRANGEMENT AND METHOD FOR THE QUANTITATIVE AND QUALITATIVE ANALYSIS OF PARTICLES IN GASES |
US6955075B2 (en) * | 2002-11-04 | 2005-10-18 | Westinghouse Savannah River Co., Llc | Portable liquid collection electrostatic precipitator |
US7168292B2 (en) * | 2003-05-15 | 2007-01-30 | The Regents Of The University Of California | Apparatus for particulate matter analysis |
US7174767B2 (en) * | 2003-12-01 | 2007-02-13 | Sensors, Inc. | Particulate matter analyzer and method of analysis |
US7534288B2 (en) * | 2006-04-07 | 2009-05-19 | Massachusetts Institute Of Technology | High performance electrostatic precipitator |
US8109161B2 (en) * | 2008-02-27 | 2012-02-07 | Baker Hughes Incorporated | Methods and apparatus for monitoring deposit formation in gas systems |
DE102008059113A1 (en) | 2008-11-26 | 2010-05-27 | Eads Deutschland Gmbh | Device for collecting strongly electron-affine particles |
CN105158027B (en) * | 2015-08-27 | 2018-02-23 | 太原理工大学 | A kind of glance coal volatile content collects measure device and its assay method |
JP6502528B2 (en) * | 2015-09-22 | 2019-04-17 | アプライド マテリアルズ インコーポレイテッドApplied Materials,Incorporated | Diffusion barrier for oscillating quartz, measuring assembly for measuring deposition rate and method thereof |
DE102016123455B4 (en) * | 2016-12-05 | 2022-09-01 | Infineon Technologies Ag | Device for analyzing the fine dust particle content of an aerosol |
WO2018118934A1 (en) * | 2016-12-19 | 2018-06-28 | Massachusetts Institute Of Technology | Systems and methods for monitoring air particulate matter |
CN110687005B (en) * | 2019-10-12 | 2022-06-24 | 东莞维科电池有限公司 | Quantitative analysis method and application of positive pole piece active substance |
CN111811980B (en) * | 2020-08-17 | 2021-02-02 | 苏州英柏检测技术有限公司 | Portable diesel vehicle tail gas detection device |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3561253A (en) * | 1969-03-26 | 1971-02-09 | Thermo Systems Inc | Apparatus and method of measurement of particulate mass |
US4561286A (en) * | 1983-07-13 | 1985-12-31 | Laboratoire Suisse De Recherches Horlogeres | Piezoelectric contamination detector |
US4917499A (en) * | 1986-10-03 | 1990-04-17 | Hughes Aircraft Company | Apparatus for analyzing contamination |
US5056355A (en) * | 1988-12-03 | 1991-10-15 | Murgitroyd & Company | Dust monitors and dust monitoring |
US5401468A (en) * | 1990-11-13 | 1995-03-28 | Rupprecht & Patashnick Company | Dual flow path carbon particulate monitor |
Family Cites Families (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3478573A (en) * | 1965-07-29 | 1969-11-18 | Exxon Research Engineering Co | Integral heater piezoelectric devices |
GB1205324A (en) * | 1967-01-23 | 1970-09-16 | Unisearch Ltd | Improved method and apparatus for measuring the electrical properties of gases and dispersoids |
US3715911A (en) * | 1970-05-11 | 1973-02-13 | Susquehanna Corp | Apparatus for sensing air-borne particulate matter |
FR2298099A1 (en) * | 1975-01-15 | 1976-08-13 | Aquitaine Petrole | DEVICE FOR MEASURING THE MASS OF PARTICLES OF AN AEROSOL PER UNIT OF VOLUME |
GB1494451A (en) * | 1975-02-12 | 1977-12-07 | Smidth & Co As F L | Apparatus for measuring the content of dust in gases |
US4166379A (en) * | 1975-03-11 | 1979-09-04 | Pye Limited | Apparatus for the detection of volatile organic substances |
US4248386A (en) * | 1977-10-31 | 1981-02-03 | Ransburg Corporation | Electrostatic deposition apparatus |
US4294105A (en) * | 1980-04-08 | 1981-10-13 | Exxon Research & Engineering Co. | Mass sensing element |
EP0038637A1 (en) * | 1980-04-18 | 1981-10-28 | Secretary of State for Social Services in Her Britannic Majesty's Gov. of the U.K. of Great Britain and Northern Ireland | Improvements in or relating to a method and apparatus for detecting the presence of contaminants in a gaseous carrier |
US4309199A (en) * | 1980-05-15 | 1982-01-05 | Nagatoshi Suzuki | Air cleaner for engines |
US4656832A (en) * | 1982-09-30 | 1987-04-14 | Nippondenso Co., Ltd. | Detector for particulate density and filter with detector for particulate density |
SU1564520A1 (en) * | 1986-02-24 | 1990-05-15 | Всесоюзный Научно-Исследовательский И Проектно-Конструкторский Институт Охраны Окружающей Природной Среды В Угольной Промышленности | Dust content meter |
US4764186A (en) * | 1987-03-23 | 1988-08-16 | The United States Of America As Represented By The United States Department Of Energy | Particle impactor assembly for size selective high volume air sampler |
JPS63261137A (en) * | 1987-04-17 | 1988-10-27 | Agency Of Ind Science & Technol | Mass measuring instrument for fine particulate material |
US5042288A (en) * | 1990-05-25 | 1991-08-27 | The United States Of America As Represented By The Secretary Of The Army | Method of sensing contamination in the atmosphere |
US5110747A (en) * | 1990-11-13 | 1992-05-05 | Rupprecht & Patashnick Company, Inc. | Diesel particulate monitor |
JPH0830673B2 (en) * | 1990-11-26 | 1996-03-27 | 柴田科学器械工業株式会社 | How to measure the mass concentration of dust particles |
US5349844A (en) * | 1992-09-11 | 1994-09-27 | Trc Companies, Inc. | System and method for resonant filter mass monitoring |
US5476002A (en) * | 1993-07-22 | 1995-12-19 | Femtometrics, Inc. | High sensitivity real-time NVR monitor |
JP3354217B2 (en) * | 1993-07-30 | 2002-12-09 | 柴田科学株式会社 | How to measure the mass concentration of dust particles in a gas |
JP3146429B2 (en) * | 1993-09-09 | 2001-03-19 | 日本鋼管株式会社 | Automatic measurement device for dust concentration in exhaust gas |
US5511409A (en) * | 1994-09-19 | 1996-04-30 | Knaebel; Kent S. | Measurement of emission levels in a gas stream |
-
1995
- 1995-11-21 GB GBGB9523812.7A patent/GB9523812D0/en active Pending
-
1996
- 1996-11-20 EP EP03010874A patent/EP1353167A1/en not_active Withdrawn
- 1996-11-20 DE DE69631465T patent/DE69631465T2/en not_active Expired - Fee Related
- 1996-11-20 US US08/753,105 patent/US5892141A/en not_active Expired - Fee Related
- 1996-11-20 AT AT96308384T patent/ATE259062T1/en not_active IP Right Cessation
- 1996-11-20 EP EP96308384A patent/EP0779510B1/en not_active Expired - Lifetime
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3561253A (en) * | 1969-03-26 | 1971-02-09 | Thermo Systems Inc | Apparatus and method of measurement of particulate mass |
US4561286A (en) * | 1983-07-13 | 1985-12-31 | Laboratoire Suisse De Recherches Horlogeres | Piezoelectric contamination detector |
US4917499A (en) * | 1986-10-03 | 1990-04-17 | Hughes Aircraft Company | Apparatus for analyzing contamination |
US5056355A (en) * | 1988-12-03 | 1991-10-15 | Murgitroyd & Company | Dust monitors and dust monitoring |
US5401468A (en) * | 1990-11-13 | 1995-03-28 | Rupprecht & Patashnick Company | Dual flow path carbon particulate monitor |
Cited By (32)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2000046584A2 (en) * | 1999-02-02 | 2000-08-10 | Rupprecht & Patashnick Company, Inc. | Differential particulate mass monitor with intrinsic correction for volatilization losses |
WO2000046584A3 (en) * | 1999-02-02 | 2000-12-07 | Rupprecht & Patashnick Co | Differential particulate mass monitor with intrinsic correction for volatilization losses |
US6205842B1 (en) | 1999-02-02 | 2001-03-27 | Rupprecht & Patashnick Company, Inc. | Differential particulate mass monitor with intrinsic correction for volatilization losses |
US6502450B1 (en) | 1999-05-10 | 2003-01-07 | Rupprecht & Patashnik Company, Inc. | Single detector differential particulate mass monitor with intrinsic correction for volatilization losses |
EP1059521A2 (en) * | 1999-06-07 | 2000-12-13 | MIE, Inc | System and method for continuous monitoring of particulates |
EP1059521A3 (en) * | 1999-06-07 | 2003-05-21 | MIE, Inc | System and method for continuous monitoring of particulates |
WO2001001110A1 (en) * | 1999-06-23 | 2001-01-04 | Avl List Gmbh | Arrangement for quantitative and qualitative analysis of particles in gases |
US7171844B2 (en) | 2000-04-05 | 2007-02-06 | The Charles Stark Draper Laboratory, Inc. | Apparatus and method for measuring the mass of a substance |
JP2003532056A (en) * | 2000-04-05 | 2003-10-28 | ザ チャールズ スターク ドレイパー ラボラトリー インク | Apparatus and method for measuring mass of substance |
EP1251344A2 (en) * | 2001-04-18 | 2002-10-23 | AVL List GmbH | Process of measuring aerosol particles in gas samples |
EP1251344B1 (en) * | 2001-04-18 | 2007-01-03 | AVL List GmbH | Process for measuring aerosol particles in gas samples |
EP1283419A3 (en) * | 2001-08-11 | 2004-12-22 | Robert Bosch Gmbh | Device for determining the concentration of particles in a exhaust gas flow |
US7117718B2 (en) | 2001-08-11 | 2006-10-10 | Robert Bosch Gmbh | Device for ascertaining a particle concentration in an exhaust gas flow |
EP1283419A2 (en) * | 2001-08-11 | 2003-02-12 | Robert Bosch Gmbh | Device for determining the concentration of particles in a exhaust gas flow |
EP1316796A1 (en) * | 2001-11-26 | 2003-06-04 | AVL List GmbH | Apparatus and method of determining the non-volatile portion of aerosol particles in a gas sample |
WO2003100390A2 (en) * | 2002-05-24 | 2003-12-04 | Symyx Technologies, Inc. | High throughput microbalance and methods of using same |
WO2003100390A3 (en) * | 2002-05-24 | 2004-02-05 | Symyx Technologies Inc | High throughput microbalance and methods of using same |
US6928877B2 (en) | 2002-05-24 | 2005-08-16 | Symyx Technologies, Inc. | High throughput microbalance and methods of using same |
US7207211B2 (en) | 2002-05-24 | 2007-04-24 | Symyx Technologies, Inc. | High throughput microbalance and methods of using same |
US7273316B2 (en) | 2003-01-23 | 2007-09-25 | Institut National Polytechnique De Toulouse | Device and method for thermogravimetrically testing the behavior of a solid material |
FR2850460A1 (en) * | 2003-01-23 | 2004-07-30 | Toulouse Inst Nat Polytech | Method for testing materials by thermogravimetry, comprises heating and cooling samples in presence of controlled atmosphere and weighing them during the cycles with high precision integral balances |
WO2004068102A2 (en) * | 2003-01-23 | 2004-08-12 | Institut National Polytechnique De Toulouse | Device and method for thermogravimetrically testing the behavior of a solid material |
WO2004068102A3 (en) * | 2003-01-23 | 2004-09-10 | Toulouse Inst Nat Polytech | Device and method for thermogravimetrically testing the behavior of a solid material |
US8732938B2 (en) | 2003-03-21 | 2014-05-27 | MEAS France | Method of packaging a sensor |
US7721590B2 (en) | 2003-03-21 | 2010-05-25 | MEAS France | Resonator sensor assembly |
JP2005172831A (en) * | 2003-12-10 | 2005-06-30 | Robert Bosch Gmbh | Apparatus for detecting particles in exhaust gas |
DE102006032106A1 (en) * | 2006-07-11 | 2008-01-17 | Siemens Ag | Soot sensor and operating method |
GB2506991A (en) * | 2012-09-21 | 2014-04-16 | Msp Corp | Measuring the mass of particulate matter in a gas |
US11085861B1 (en) | 2014-03-03 | 2021-08-10 | Msp Corporation | Apparatus for real-time size-distributed measurement of aerosol mass concentration |
WO2015189230A1 (en) * | 2014-06-10 | 2015-12-17 | Koninklijke Philips N.V. | Aerosol mass sensor and sensing method |
CN106415235A (en) * | 2014-06-10 | 2017-02-15 | 皇家飞利浦有限公司 | Aerosol mass sensor and sensing method |
CN110426310A (en) * | 2019-07-31 | 2019-11-08 | 长春黄金研究院有限公司 | A kind of Fire Assaying analysis method |
Also Published As
Publication number | Publication date |
---|---|
DE69631465T2 (en) | 2004-12-02 |
ATE259062T1 (en) | 2004-02-15 |
GB9523812D0 (en) | 1996-01-24 |
DE69631465D1 (en) | 2004-03-11 |
US5892141A (en) | 1999-04-06 |
EP0779510A3 (en) | 1998-05-27 |
EP1353167A1 (en) | 2003-10-15 |
EP0779510B1 (en) | 2004-02-04 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US5892141A (en) | Method and apparatus for analysis of particulate content of gases | |
Tobias et al. | Chemical analysis of diesel engine nanoparticles using a nano-DMA/thermal desorption particle beam mass spectrometer | |
US5731510A (en) | Multi-gas sensor systems for automotive emissions measurement | |
Chase et al. | PM measurement artifact: organic vapor deposition on different filter media | |
Rickeard et al. | Exhaust particulate size distribution: vehicle and fuel influences in light duty vehicles | |
US4916384A (en) | Apparatus for measuring the soot particles contained in the exhaust gas emitted from diesel engines | |
Silva et al. | On-line characterization of individual particles from automobile emissions | |
Vouitsis et al. | Particulate matter mass measurements for low emitting diesel powered vehicles: what's next? | |
Maricq et al. | Measuring particulate mass emissions with the electrical low pressure impactor | |
Mujahid et al. | Monitoring automotive oil degradation: analytical tools and onboard sensing technologies | |
Artelt et al. | Engine test bench experiments to determine platinum emissions from three-way catalytic converters | |
Schweyer et al. | An acoustic plate mode sensor for aqueous mercury | |
Wei et al. | The on-board PM mass calibration for the real-time PM mass measurement | |
Maricq et al. | A comparison of tailpipe, dilution tunnel, and wind tunnel data in measuring motor vehicle PM | |
Japar et al. | Real-time measurements of diesel vehicle exhaust particulate using photoacoustic spectroscopy and total light extinction | |
Mueller et al. | Concentration of fine particles and lead in car exhaust | |
Klein et al. | Diesel particulate emissions of passenger cars-New insights into structural changes during the process of exhaust aftertreatment using diesel oxidation catalysts | |
Swanson et al. | Alternatives to the gravimetric method for quantification of diesel particulate matter near the lower level of detection | |
Mörsch et al. | Investigation of alternative methods to determine particulate mass emissions | |
Liu et al. | A source dilution sampling system for characterization of engine emissions under transient or steady-state operation | |
CN114062478B (en) | Method for realizing self-verification of particle pollutant source analysis | |
Booker et al. | Road test of an on-board particulate matter mass measurement system | |
Theisen et al. | Elemental analysis of airborne dust samples with TXRF: Comparison of oxygen-plasma ashing on sapphire carriers and acid digestion for sample preparation | |
RU2525051C1 (en) | Method of measuring parameters of internal combustion engine exhaust gases | |
JP3631373B2 (en) | Immunoassay and immunoassay apparatus |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A2 Designated state(s): AT DE FR GB IE IT NL SE |
|
PUAL | Search report despatched |
Free format text: ORIGINAL CODE: 0009013 |
|
AK | Designated contracting states |
Kind code of ref document: A3 Designated state(s): AT DE FR GB IE IT NL SE |
|
17P | Request for examination filed |
Effective date: 19981126 |
|
RAP1 | Party data changed (applicant data changed or rights of an application transferred) |
Owner name: SNAP-ON EQUIPMENT LIMITED |
|
RAP3 | Party data changed (applicant data changed or rights of an application transferred) |
Owner name: SNAP-ON EQUIPMENT LIMITED |
|
17Q | First examination report despatched |
Effective date: 20010205 |
|
GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
GRAS | Grant fee paid |
Free format text: ORIGINAL CODE: EPIDOSNIGR3 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AT DE FR GB IE IT NL SE |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20040204 Ref country code: IT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED. Effective date: 20040204 Ref country code: AT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20040204 |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: FG4D |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: FG4D |
|
REF | Corresponds to: |
Ref document number: 69631465 Country of ref document: DE Date of ref document: 20040311 Kind code of ref document: P |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SE Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20040504 |
|
NLV1 | Nl: lapsed or annulled due to failure to fulfill the requirements of art. 29p and 29m of the patents act | ||
ET | Fr: translation filed | ||
PLBQ | Unpublished change to opponent data |
Free format text: ORIGINAL CODE: EPIDOS OPPO |
|
PLBI | Opposition filed |
Free format text: ORIGINAL CODE: 0009260 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20041120 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20041122 |
|
PLAX | Notice of opposition and request to file observation + time limit sent |
Free format text: ORIGINAL CODE: EPIDOSNOBS2 |
|
26 | Opposition filed |
Opponent name: AVL LIST GMBH Effective date: 20041102 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20050601 |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 20041120 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20050729 |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: MM4A |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST |
|
PLCK | Communication despatched that opposition was rejected |
Free format text: ORIGINAL CODE: EPIDOSNREJ1 |
|
PLBN | Opposition rejected |
Free format text: ORIGINAL CODE: 0009273 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: OPPOSITION REJECTED |
|
27O | Opposition rejected |
Effective date: 20060405 |